This invention relates to a connecting rod gearing c for the installation into a stepped profiled slot in a window or frame, etc. Such a window or frame has two connecting rods, oppositely shiftable with respect to one another, under a cover rail. In each case, two thrust links, equipped with engagement teeth, are guided in a housing and held in engagement from opposite sides with a pinion. The housing consists of the flat cover rail of the connecting rod mounting and of a cross-sectionally U-shaped channel resting on the back of the rail. The channel has a smaller width than that of the cover rail. The rotational plane of the pinion lies parallel to the plane of the cover rail of the housing.
Connecting rod gearings for windows, doors, etc. with two oppositely shiftable connecting rods have long been known, as can be learned, for example, from the German patent Nos. 604,687 and 677,389. The pinion meshing with the engagement teeth of the thrust links or connecting rods can be used directly as the driving link of the connecting rod gearing when the pinion is brought into working connection with a control handle (for example, a control grip (German patent No. 604,687). On the other hand, the pinion meshing with the engagement teeth of the thrust links or connecting rods may also be installed so that merely a thrust-direction reversal gearing is formed, by means of which the thrust motion derived from one of the two connecting rods is converted into a motion opposite thereto at the other connecting rod (German patent No. 677,389).
Prior connecting rod gearings for windows, doors, etc. (German references DE-GM1940854 and DE-AS2557303), not only display the initially mentioned features, but also have a configuration which permits their installation in profiled slots at the folding faces of the wings or frames of windows, doors, etc. Such slots have an inner slot step, with a width of 12 mm. and a depth of 9 mm., as well as an outer slot step, with a width of 16 mm. and a depth of, at most, 2.5 mm.
German references DE-GM1940854 and DE-AS2557303 show how such connecting rod gearings, for the transmission of any adjusting forces which occur, can be designed to be sufficiently stable and therefore functionally reliable when they are used as pure thrust-direction reversal gearing. In these cases, however, the effective diameter of the pinion meshing with the thrust links or connecting rods has no direct effect on the regulating distance through which the connecting rods have to pass. This is because these distances are determined from an additional actuating gearing which is installed at another place and acts upon one of the connecting rods. The angle of rotation of the pinions, which act here solely and specifically as reversal links, is practically unlimited on such thrust-direction reversal gearings.
However, there are times when the species-appropriate type of pinion is simultaneously used on connecting rod gearings for windows, doors, etc. as a driving link for actuation of a connecting rod mounting. It is connected with an operating handle, for example, a control grip. In such cases, the angle of rotation of the pinion is limited as a rule to 90 degrees, or maximally 180 degrees, for technical reasons having to do with service.
Since the maximal diameter of the pinions provided in the installation design of prior known connecting rod gearings (DE-GM1940854 and DE-AS2557303) cannot be greater than the 12 mm. width of the lower slot step of the profiled slot provided in the wing or frame, in each case only small regulating distances can be imparted to the connecting rods which are moved oppositely to one another by means of the pinion. Specifically, on a 90 degree rotation of the pinion, the regulating distance for each one of the connecting rods is approximately 7 mm., while on a 180 degree rotation of the pinion, it can attain 14 mm. at most.
Nowadays for practical application and especially for reliability, regulating distances for connecting rods and mountings for windows, doors, etc. are required to amount to, at a minimum, 10 mm. and should preferably reach 20 mm. Given the installation dimensions of specific types of connecting rod gearings, these regulating distances would be attainable only by using angles of rotation for the pinions which would be either 130 degrees or 260 degrees. However, providing connecting rod gearings with control grips acting as service handles which employ angles of rotation other than 90 degrees of 180 degrees is highly unusual and not adaptable for practical use.
It is, therefore, a primary aim of the invention to include a species-appropriate connecting rod gearing so that its driving links can be manufactured despite a limited cross-sectional dimension of the profiled slots which serve for the take-up of the connecting rod mountings. The object is to allow fabrication by customary methods in the fittings industry and to insure a strong, durable, functionally reliable fitting.
A further object of the invention is to create a connecting rod gearing of the above-mentioned construction which makes use of the oppositely directed coupling of the two thrust links or connecting rods by means of one pinion only and which only needs to pass through an angle of rotation of 90 degrees for a regulating distance of at least 10 mm. and at most, an angle of rotation of 180 degrees for a regulating distance of at least 20 mm.